Russia installed a radio-jammer that interferes with the signals that direct GPS-guided munitions. Last week, Ukraine blew it up ... with a GPS-guided bomb.
As another commenter said, I don’t think cryptography is the main problem.
You’ve got to be able to modulate some numbers out of the radio signal first before you need to be concerned if it’s encrypted or not.
GPS signals from power conserving satellites are so weak that I’d imagine that overwhelming them with noise on all frequencies would be the easy answer. (Although there’s a Big Brain hyper-cunning answer to that…).
As another commenter said, I don’t think cryptography is the main problem.
You’ve got to be able to modulate some numbers out of the radio signal first before you need to be concerned if it’s encrypted or not.
GPS signals from power conserving satellites are so weak that I’d imagine that overwhelming them with noise on all frequencies would be the easy answer. (Although there’s a Big Brain hyper-cunning answer to that…).